The present disclosure relates to a developer case for storing developer, and an image forming apparatus to which the developer case is attached.
In an image forming apparatus, that forms an image on a sheet using toner (developer), a developer case such as a toner container is necessary. A toner container stores toner to be supplied to a developing unit, and is detachably attached to an image forming apparatus. In general, a toner container has a main body that serves as a storage space for toner, a discharge port located in the bottom wall of the main body, a transport screw that transports toner toward the discharge port, and an agitating paddle that moves toner in the main body. The spiral of the transport screw has a double spiral structure consisting of a radially inner spiral and a radially outer spiral.
One of the important considerations in a toner container is to discharge toner through the discharge port such that no toner remains in the main body. However, the shape of a toner container is determined based not only on the ease of toner discharge, but also the design of the image forming apparatus. For this reason, depending on the shape of a container, toner can become packed in the vicinity of the discharge port, and the discharge of toner hindered.